Method for processing delay coking liquid hydrocarbons with gas fractional distillation apparatus

Abstract

The present invention discloses a method for producing propylene, propane and C4 fraction by pre-processing a liquid state hydrocarbon generated by a delayed coker and processing the liquid state hydrocarbon as a raw material of a gas fractionation plant. The method is comprises the following steps that: the coked liquid state hydrocarbon in which hydrogen sulfide is removed by an amine solution is subjected to sodafining and water washing to remove thiol and a small amount of water before entering a gas separation device; and then the liquid state hydrocarbon enters a COS hydrolyzer to desulfurate; afterward, hydrogen sulfide generated from the hydrolization is removed; and then the liquid state hydrocarbon enters the gas fractionation plant as a material to be processed.

Description

Technical field [0001] The method relates to a method for pretreating liquid hydrocarbons produced by a delayed coking unit, and then processing them as raw materials for a gas fractionation unit to produce propylene, propane and carbon four fractions. Background technique [0002] The liquid hydrocarbons produced by the delayed coking unit contain a certain concentration of propylene, and the sulfur content is also relatively high, and the sulfur forms are complex, including mercaptan, carbonyl sulfide, sulfide, etc., first use amine liquid to desulfurize and then use alkali After liquid sweetening, there is still a high sulfur content. In this way, if it is not further processed, it is directly sent to the gas fractionation unit as a raw material for separation; or mixed with liquid hydrocarbons from the catalytic cracking unit and then sent to the gas fractionation unit for separation, the sulfur content in the product propylene of the gas fractionation unit will exceed t...